A proposal for new diagnostic criteria for ALS Shefner, Jeremy M.; Al-Chalabi, Ammar; Baker, Mark R. ...
Clinical neurophysiology,
August 2020, 2020-08-00, 20200801, Letnik:
131, Številka:
8
Journal Article
One of the major consequences of the COVID-19 pandemic has been the significant incidence of persistent fatigue following resolution of an acute infection (i.e. post-COVID fatigue). We have shown ...previously that, in comparison to healthy controls, those suffering from post-COVID fatigue exhibit changes in muscle physiology, cortical circuitry, and autonomic function. Whether these changes preceded infection, potentially predisposing people to developing post-COVID fatigue, or whether the changes were a consequence of infection was unclear. Here we present results of a 12-month longitudinal study of 18 participants from the same cohort of post-COVID fatigue sufferers to investigate these correlates of fatigue over time. We report improvements in self-perception of the impact of fatigue via questionnaires, as well as significant improvements in objective measures of peripheral muscle fatigue and autonomic function, bringing them closer to healthy controls. Additionally, we found reductions in muscle twitch tension rise times, becoming faster than controls, suggesting that the improvement in muscle fatigability might be due to a process of adaptation rather than simply a return to baseline function.
To determine the incidence of chronic medical conditions of men with infertility.
Retrospective cohort study.
Not applicable.
Subjects contained within the Truven Health MarketScan claims database ...from 2001 to 2009.
Not applicable.
The development of chronic medical conditions including hypertension, diabetes, hyperlipidemia, renal disease, pulmonary disease, liver disease, depression, peripheral vascular disease, cerebrovascular disease, heart disease, injury, alcohol abuse, drug abuse, anxiety disorders, and bipolar disorder.
In all, 13,027 men diagnosed with male factor infertility were identified with an additional 23,860 receiving only fertility testing. The average age was 33.1 years for men diagnosed with infertility and 32.8 years for men receiving testing alone. After adjusting for confounding factors, men diagnosed with male factor infertility had a higher risk of developing diabetes (hazard ratio HR 1.30, 95% confidence interval CI 1.10-1.53), ischemic heart disease (HR 1.48, 95% CI 1.19-1.84), alcohol abuse (HR 1.48, 95% CI 1.07-2.05), and drug abuse (1.67, 95% CI 1.06-2.63) compared with men who only received infertility testing. Similar patterns were identified when comparing those with male factor infertility to vasectomized men. The association between male factor infertility and later health outcomes were strongest for men with longer follow-up.
In this cohort of patients in a national insurance database, men diagnosed with male factor infertility had a significantly higher risk of adverse health outcomes in the years after an infertility evaluation. These findings suggest the overall importance of men's reproductive health and warrant additional investigation to understand the association and identify interventions to improve outcomes for these patients.
We investigated beta-band intermuscular coherence (IMC) in 92 healthy adults stratified by decade of age, and analysed variability between and within subjects. In the dominant upper limb, IMC was ...estimated between extensor digitorum communis and first dorsal interosseous as well as between flexor digitorum superficialis and first dorsal interosseous. In the ipsilateral lower limb, IMC was measured between medial gastrocnemius and extensor digitorum brevis as well as between tibialis anterior and extensor digitorum brevis. Age-related changes in IMC were analysed with age as a continuous variable or binned by decade. Intrasession variance of IMC was examined by dividing sessions into pairs of epochs and comparing coherence estimates between these pairs. Eight volunteers returned for a further session after one year, allowing us to compare intrasession and intersession variance. We found no age-related changes in IMC amplitude across almost six decades of age, allowing us to collate data from all ages into an aggregate normative dataset. Interindividual variability ranged over two orders of magnitude. Intrasession variance was significantly greater than expected from statistical variability alone, and intersession variance was even larger. Potential contributors include fluctuations in task performance, differences in electrode montage and short-term random variation in central coupling. These factors require further exploration and, where possible, minimisation. This study provides evidence that coherence is remarkably robust to senescent changes in the nervous system and provides a large normative dataset for future applications of IMC as a biomarker in disease states.
Non‐technical summary Neural activity in parts of the cerebral cortex related to movement oscillates at frequencies around 20 Hz. These oscillations are correlated with similar rhythms in contracting ...muscles on the opposite side of the body. In this work, we used an analysis method called directed coherence to investigate the direction of oscillatory coupling. We find that oscillations travel not only from cortex to muscle (as expected for a motor command), but also back from muscle to cortex (reflecting sensory input). This oscillatory loop may allow the cortex to measure features of the limb state, integrating sensory inflow with the motor command.
Corticomuscular coherence in the beta frequency band (15–30 Hz) has been demonstrated in both humans and monkeys, but its origin and functional role are still unclear. Phase–frequency plots produced by traditional coherence analysis are often complex. Some subjects show a clear linear phase–frequency relationship (indicative of a fixed delay) but give shorter delays than expected; others show a constant phase across frequencies. Recent evidence suggests that oscillations may be travelling around a peripheral sensorimotor loop. We recorded sensorimotor EEGs and EMGs from three intrinsic hand muscles in human subjects performing a precision grip task, and applied directed coherence (Granger causality) analysis to explore this system. Directed coherence was significant in both descending (EEG→EMG) and ascending (EMG→EEG) directions at beta frequencies. Average phase delays of 26.4 ms for the EEG→EMG direction and 29.5 ms for the EMG→EEG direction were closer to the expected conduction times for these pathways than the average delays estimated from coherence phase (7.9 ms). Subjects were sub‐divided into different groups, based on the sign of the slope of the linear relation between corticomuscular coherence phase and frequency (positive, negative or zero). Analysis separated by these groups suggested that different relative magnitudes of EEG→EMG and EMG→EEG directed coherence might underlie the observed inter‐individual differences in coherence phase. These results confirm the complex nature of corticomuscular coherence with contributions from both descending and ascending pathways.
To develop recommendations concerning the management of male breast cancer.
ASCO convened an Expert Panel to develop recommendations based on a systematic review and a formal consensus process.
...Twenty-six descriptive reports or observational studies met eligibility criteria and formed the evidentiary basis for the recommendations.
Many of the management approaches used for men with breast cancer are like those used for women. Men with hormone receptor-positive breast cancer who are candidates for adjuvant endocrine therapy should be offered tamoxifen for an initial duration of five years; those with a contraindication to tamoxifen may be offered a gonadotropin-releasing hormone agonist/antagonist plus aromatase inhibitor. Men who have completed five years of tamoxifen, have tolerated therapy, and still have a high risk of recurrence may be offered an additional five years of therapy. Men with early-stage disease should not be treated with bone-modifying agents to prevent recurrence, but could still receive these agents to prevent or treat osteoporosis. Men with advanced or metastatic disease should be offered endocrine therapy as first-line therapy, except in cases of visceral crisis or rapidly progressive disease. Targeted systemic therapy may be used to treat advanced or metastatic cancer using the same indications and combinations offered to women. Ipsilateral annual mammogram should be offered to men with a history of breast cancer treated with lumpectomy regardless of genetic predisposition; contralateral annual mammogram may be offered to men with a history of breast cancer and a genetic predisposing mutation. Breast magnetic resonance imaging is not recommended routinely. Genetic counseling and germline genetic testing of cancer predisposition genes should be offered to all men with breast cancer.
Since its introduction as a treatment for strabismus, botulinum toxin (BoNT) has had a phenomenal journey and is now recommended as first-line treatment for focal dystonia, despite short-term ...clinical benefits and the risks of adverse effects. To cater for the high demand across various medical specialties, at least six US Food and Drug Administration (FDA)-approved formulations of BoNT are currently available for diverse labelled indications. The toxo-pharmacological properties of these formulations are not uniform and thus should not be used interchangeably. Synthetic BoNTs and BoNTs from non-clostridial sources are not far from clinical use. Moreover, the study of mutations in naturally occurring toxins has led to modulation in the toxo-pharmacokinetic properties of BoNTs, including the duration and potency. We present an overview of the toxo-pharmacology of conventional and novel BoNT preparations, including those awaiting imminent translation from the laboratory to the clinic.
New Findings
What is the topic of this review?
The emerging condition of long COVID, its epidemiology, pathophysiological impacts on patients of different backgrounds, physiological mechanisms ...emerging as explanations of the condition, and treatment strategies being trialled. The review leads from a Physiological Society online conference on this topic.
What advances does it highlight?
Progress in understanding the pathophysiology and cellular mechanisms underlying Long COVID and potential therapeutic and management strategies.
Long COVID, the prolonged illness and fatigue suffered by a small proportion of those infected with SARS‐CoV‐2, is placing an increasing burden on individuals and society. A Physiological Society virtual meeting in February 2022 brought clinicians and researchers together to discuss the current understanding of long COVID mechanisms, risk factors and recovery. This review highlights the themes arising from that meeting. It considers the nature of long COVID, exploring its links with other post‐viral illnesses such as myalgic encephalomyelitis/chronic fatigue syndrome, and highlights how long COVID research can help us better support those suffering from all post‐viral syndromes. Long COVID research started particularly swiftly in populations routinely monitoring their physical performance – namely the military and elite athletes. The review highlights how the high degree of diagnosis, intervention and monitoring of success in these active populations can suggest management strategies for the wider population. We then consider how a key component of performance monitoring in active populations, cardiopulmonary exercise training, has revealed long COVID‐related changes in physiology – including alterations in peripheral muscle function, ventilatory inefficiency and autonomic dysfunction. The nature and impact of dysautonomia are further discussed in relation to postural orthostatic tachycardia syndrome, fatigue and treatment strategies that aim to combat sympathetic overactivation by stimulating the vagus nerve. We then interrogate the mechanisms that underlie long COVID symptoms, with a focus on impaired oxygen delivery due to micro‐clotting and disruption of cellular energy metabolism, before considering treatment strategies that indirectly or directly tackle these mechanisms. These include remote inspiratory muscle training and integrated care pathways that combine rehabilitation and drug interventions with research into long COVID healthcare access across different populations. Overall, this review showcases how physiological research reveals the changes that occur in long COVID and how different therapeutic strategies are being developed and tested to combat this condition.
Paroxysmal extreme pain disorder (PEPD), previously known as familial rectal pain (FRP, or OMIM 167400), is an inherited condition characterized by paroxysms of rectal, ocular, or submandibular pain ...with flushing. A genome-wide linkage search followed by mutational analysis of the candidate gene
SCN9A, which encodes hNa
v1.7, identified eight missense mutations in 11 families and 2 sporadic cases. Functional analysis in vitro of three of these mutant Na
v1.7 channels revealed a reduction in fast inactivation, leading to persistent sodium current. Other mutations in
SCN9A associated with more negative activation thresholds are known to cause primary erythermalgia (PE). Carbamazepine, a drug that is effective in PEPD, but not PE, showed selective block of persistent current associated with PEPD mutants, but did not affect the negative activation threshold of a PE mutant. PEPD and PE are allelic variants with distinct underlying biophysical mechanisms and represent a separate class of peripheral neuronal sodium channelopathy.